1. Field of the Invention
The present invention relates to a lever-type connector, in particular an electrical connector having housings containing electrical elements which are connected when the housings are fitted together.
2. Description of the Related Art
FIGS. 7 through 9 show a conventional lever-type connector. A lever 101 is rotatably supported by a first connector housing 100 which fits into a mating second connector housing 110 in order to make an electrical connection between arrays of terminals in the housings 100,110. Cam pins 111 on the second connector housing 110 engage cam groove 102 of the lever 101. The lever 101 has a pair of plate-shaped arm portions 104, one on each side of the housing, extending to an operation portion 103. The operation portion 103 preferably connects the plate-shaped arm portions 104 together in a substantially rigid manner. This allows the plate-shaped arm portions 104 to more easily be rotated in unison. The cam grooves 102 are formed in the respective arm portions 104.
When fitting the two connector housings 100, 110 to each other, the lever 101 is set in a predetermined waiting posture with the entrance 102A of the cam groove 102 open toward the second connector housing 110. In this state, the connector housings 100, 110 are approached to each other parallel to the surfaces of the arm portions 104 and partially fitted into each other so that the cam pin 111 penetrates into the entrance 102A of the cam groove 102 on each side. The lever 101 is rotated, drawing the connector housings 100, 110 tightly together by a cam action due to the engagement between the cam grooves 102 and the cam pins 111. This kind of lever-type connector is disclosed in JP-A-6-275337.
Let it be supposed that in fitting the connector housings 100, 110 together, the lever 101 is not set at the waiting posture, so that the entrance 102A of the cam groove 102 is not at its position to receive the pin 111. In this case, when the connector housings 100, 110 are approached to each other, the periphery of the cam pin 111 collides with the peripheral edge of the arm portion 104. The operator thus discovers that the lever 101 is located at an inappropriate position. However, if the operator does not notice that the periphery of the cam pin 111 has collided with the peripheral edge of the arm portion 104 and proceeds with the fitting operation forcibly, the arm portion 104 may deform outwardly, thus riding over the cam pin 111. As a result, the arm portions 104 disengage from the peripheral surfaces of the cam pins 111, and the connector housings 100, 110 may be fitted in each other incompletely, with the cam pins 111 and the cam grooves 102 not in engagement with each other, as shown in FIGS. 8 and 9.
U.S. Pat. No. 5,476,390 shows a connector similar to that of FIGS. 7 to 9, in which the cam pins have a chamfer at their extremity, which may tend to encourage over-riding of the lever on the pin.